Abstract: A vacuum monitoring device of a vacuum circuit breaker with a line of a vacuum valve led out to the external of a metal tank through a bushing having a shield working as a low-pass filter, includes: a first antenna; a second antenna; a first and a second detection portion measuring intensity of an electromagnetic wave detected by the antennas; and a determination portion determining a vacuum deterioration of the circuit breaker by comparing the intensity of the electromagnetic wave detected by the first and the second detection portions, wherein the first and second detection portion include frequency filters passing a frequency band, of electromagnetic waves resulting from discharges occurring when the vacuum valve deteriorates in vacuum, which is attenuated by the shield.

Abstract: Processes and apparatuses are provided for contactless measuring or monitoring in-situ and in real time composition or other electromagnetic impedance correlated properties of liquid or gaseous substances or bulk materials. One or more apparatus may include a resonance type impedance sensor having at least two coils, at least one coil of the at least two coils being at least one excitation coil connectable to at least one alternating current source with frequency sweep, at least one other coil of the at least two coils being at least one sensing coil connectable to at least one data processing system. The one or more methods may include calculating changes in amplitude and resonant frequency induced by electromagnetic interaction between said sensor and object to determine impedance of said object under test; and matching said impedance with predetermined calibration data to determine said chemical or physical properties of said object under test.

Abstract: A fully-functional radio receiver fabricated from a single nanotube is being disclosed. Simultaneously, a single nanotube can perform the functions of all major components of a radio: antenna, tunable band-pass filter, amplifier, and demodulator. A DC voltage source, as supplied by a battery, can power the radio. Using carrier waves in the commercially relevant 40-400 MHz range and both frequency and amplitude modulation techniques, successful music and voice reception has been demonstrated. Also disclosed are a radio transmitter and a mass sensor using a nanotube resonator device.

Abstract: A sensor interface circuit is provided for resolving sensor signals from a plurality of sensors into a digital sensor signal, the sensor interface circuit comprising: a relaxation oscillator for receiving and pre-processing the sensor signals to generate an analog sensor signal, the relaxation oscillator comprising one or more dynamic circuits; and a monitoring module for receiving the analog sensor signal and generating the digital sensor signal in response thereto. There is also provided a sensor system front-end and a relaxation oscillator.

Abstract: An acoustic wave sensor employs an electromagnetic device (EMD) to transduce and amplify the response of an impedance element to a physical measurand. One embodiment uses a magnetic field sensor employing a microelectromechanical system (MEMS) capacitor to affect a change in the response of a SAW filter.

Abstract: A radio frequency communication device and methods of testing and tuning an antenna attached thereto are disclosed. A radio frequency communication device comprises internal circuitry and an antenna having a plurality of antenna segments associated therewith. Each antenna segment is associated with the antenna in either series or parallel relation through at least one of a fuse and an antifuse. In testing and tuning, a comparison is made to indicate whether the antenna is too short or too long. If the antenna is too short, an antenna segment may be attached to the antenna by initiating an antifuse. If the antenna is too long, an antenna segment may be detached from the antenna by blowing a fuse. If it is indeterminate whether the antenna is too short or too long, an antenna segment may be either attached or detached, the test repeated, and the results of the repeated test compared with the prior test to determine whether the correct action was taken.

Abstract: An apparatus for monitoring the structural integrity of a component. A monitoring structure is applied to a component that is subject to structural degradation. The monitoring structure includes an electrical conductor that becomes cracked if the component becomes structurally degraded. When the component is a ductile metal component that may be degraded by bending, the electrical conductor is formed of a brittle material that cracks when the ductile metal component is bent. When the component is a brittle ceramic heat shield wherein a crack having a critical length is of concern, the electrical conductor is located at a predetermined location wherein a critical length crack in the component will propagate into the conductor. A crack in the electrical conductor is detected with a monitoring device to indicate a degraded structural condition in the component.

Abstract: Certain characteristics of Diesel engine lubrication oil are determined. A sensor formed as a capacitor is immersed in the oil. An inductor is in series with the sensor, and a high frequency voltage with a varying frequency is applied to the resonance circuit formed by the inductor and capacitor. Resonance is sensed, and the resonant frequency and/or the resonant current are used to determine the soot content and/or the dielectric constant of the oil. The electronics temperature can be used to compensate for temperature variations in the resonant frequency and the electronics temperature and the oil temperature can be used to compensate for temperature variations in the resonant current. The compensated values are preferably used in the determination of soot content and the dielectric constant.

Abstract: Soot content in Diesel engine lubrication oil is determined using electrical resistance measurements of the oil at high frequency. A sensor in the form of a capacitor is immersed in the oil, wherein the oil serves as a dielectric between the plates. The capacitance and resistance between the plates change as a function of engine oil condition. An inductor is placed in series with the sensor, and high frequencies are sweeped over a range to find resonance where the capacitive and inductive reactances cancel. At this frequency, the resistance of the oil is measured and the condition of the oil thereby determined.

Abstract: Apparatus and methods are provided for measuring a selected optical behavior of a tunable opto-electric device by using the electrical characteristics of the opto-electronic device. The benefit of the present invention is the elimination or reduction in complexity of optical wavelength reference hardware that is currently required for wavelength referencing and locking. Accordingly, the present invention reduces the cost and complexity of the optical packaging of tunable opto-electronic telecommunication components. Furthermore, the present invention also significantly simplifies optical and electronic design of system level products with tunable opto-electronic devices.

Abstract: A radio frequency communication device and methods of testing and tuning an antenna attached thereto are disclosed. A radio frequency communication device according to the present invention is disclosed comprising internal circuitry and an antenna having a plurality of antenna segments associated therewith. Each antenna segment is associated with the antenna in either series or parallel relation through at least one of a fuse and an antifuse. In testing and tuning, a comparison is made to indicate whether the antenna is too short or too long. If the antenna is too short, an antenna segment may be attached to the antenna by initiating an antifuse. If the antenna is too long, an antenna segment may be detached from the antenna by blowing a fuse. If it is indeterminate whether the antenna is too short or too long, an antenna segment may be either attached or detached, the test repeated, and the results of the repeated test compared with the prior test to determine whether the correct action was taken.

Abstract: Apparatus for non-contact determination of wafer resistance of a semiconductor wafer includes a first sensor element, separated from a surface of the wafer by a first air gap, for capacitively coupling an AC drive signal into a portion of the wafer. A second sensor element, separated from the surface of the wafer by a second air gap, capacitively couples an AC output signal out of the wafer portion. An inductor, in series connection with the sensor elements is included in the sensor/wafer circuit. A frequency of the AC drive signal is automatically tuned to a resonant frequency at which capacitance impedance of the first air gap and of the second air gap is canceled by inductive impedance of the inductor. A voltage value of the drive signal required to drive an AC current signal of fixed magnitude through the wafer portion is automatically determined. The voltage value provides a measure of wafer resistance.

Abstract: A method and apparatus for generating an impedance spectrum which is characteristic of a sample of bodily matter in a resonant circuit and which may be used to analyse the sample.

Abstract: The effects of electromigration have been shown to lead to damage of metal electrodes of electronic devices such as thin film resonator (TFR) devices in only a few hours, for a test input power that is within the operational range of these devices. It has been determined that this failure is sensitive to the frequency of the input power. The present invention provides a method and apparatus for determining high power reliability in electronic devices, so as to enable an accurate determination of the failure time of the electronic device, and hence projected lifetime. This determination is independent from the frequency of an input power applied to the electronic device as part of the method for testing the device. Based on the above results, a TFR device has been developed, which includes a protective or electromigration-reducing layer such as titanium being deposited atop an electrode of the device.

Abstract: Apparatus are provided for measuring coating thickness. The apparatus include first and second inductors, which may be coils, and measuring the impedance of conductors by passing alternating current through the conductors. The conductors are arranged so that the first inductor may be positioned sufficiently close to a conductive surface so that its impedance changes and, when so positioned, any change in the impedance of the second inductor brought about by the surface is negligible compared to that in the impedance of the first. A microprocessor is provided and arranged to calculate a temperature compensated thickness measurement from the measured impedances of both inductors.

Abstract: Measuring the electrical resistance of a resistive body, in particular a reservoir containing a printing product such as ink. According to the invention, the resistive body is used to define a capacitance arrangement formed from a capacitive branch which includes a capacitor electrically connected to the resistive body and this is incorporated in a resonant circuit that includes a variable capacitor. The resonant circuit is supplied with a fixed frequency, and as the capacitance of the variable capacitor is varied the peak of the signal is sought. The amplitude of the peak is representative of the resistance of the resistive body.

Abstract: A circuit 17 for interfacing with a sensor 18 having a sensor input current and a modulated sensor current signal corresponding to a sensed condition. A control module 20 is coupled to the sensor 18 and receives the sensor current signal. The control module 20 converts the sensor current signal to a modulated signal having a pulse width with a duration corresponding to the sensed condition. The control module 20 counts a time corresponding to the pulse width. The time corresponds to the sensed condition.

Abstract: A sensor can detect the difference in potential between itself and the fluid into which it is immersed, a signal generated by the probe representing this difference in potential. This signal is used to activate an oscillator circuit. By varying the conditions at which current in the oscillator circuit begins to oscillate, various liquids can be detected and identified.

Abstract: A method for quantifying the permeability or conductivity of a conducting material, comprises the steps of providing a circuit including an inductor with a coil and a capacitor connected in parallel to the inductor, the coil having an interior space adapted to enclose the sample material therein; inserting the sample material into the interior space of the coil to completely enclose the sample material therein; resonating the circuit with the capacitor with capacitance C' with the inserted sample material at a resonant frequency f.sub.0 and measuring the resulting impedance, Z' of the circuit; measuring the impedance of the loaded circuit at various frequencies above and below the resonant frequency f.sub.0, and plotting a first bell-shaped curve from the measured impedances against frequencies; resonating the circuit with the capacitor with capacitance C' at a resonant frequency f.sub.x with the sample material removed from the coil and measuring the resulting impedance, Z.sub.

Abstract: A process for determining a surface resistance to microwave energy of a superconductive film provides a metallic cavity resonator whose resonator cavity is defined by metallic walls, and positioning a superconductive film whose microwave surface resistance is to be measured as at least part of a wall of the cavity. A dielectric body is applied to a surface of the film and microwave energy is coupled to the cavity through an input antenna and microwave energy is coupled out of the cavity by an output antenna at which signals are produced as a measure of the microwave surface resistance of the film.

Abstract: A device for detecting attempts at fraud by connection of an electric feed line (13) to an apparatus for reading and writing on a chip card (3) essentially comprises a resonance unit (6) coupled to a contacting element (2) of the apparatus, and a measuring device (7). In the resonance unit (6) a generator (4) which is coupled to a resonator (1) by way of an impedance converter (5) generates a standing wave. The feed line (13) disturbs the properties of the resonator (1), that being detected by the measuring device (7) and evaluated.

Abstract: A method and apparatus is disclosed for continuously monitoring the resistance of a grounding conductor to neutral conductor circuit of a power distribution system. The apparatus compares a parameter of a damped sinusoidal waveform from a shock excited resonant circuit coupled to the grounding conductor and neutral conductor at a branch circuit outlet of the power distribution system with a predetermined parameter from the same resonant circuit discharging into an external circuit having a predetermined resistance. The apparatus indicates an undesired grounding conductor resistance.

Abstract: A dielectric resonator probe for measuring surface resistance of a test material, particularly at cryogenic temperature, is provided. A dielectric resonator is mounted near to but spaced from a conductive plate and is positioned in contact with a test material. Preferably, a low-loss dielectric spacer separates the resonator from the upper plate. The dielectric resonator has a larger lower surface area than upper surface area. The dielectric resonator includes a hole therethrough for increasing mode separation and for accommodating a mounting bolt. The mounting bolt is preferably nonconductive and is coupled to a spring for resiliently mounting the resonator and spacer to the plate so as to accommodate differential thermal expansion of the components.

Abstract: A method and a device for transmitting and for measuring resistance values, is particularly provided for use in motor vehicles, for the constant control of airbag systems. In the method and device an exciter signal coupled into a secondary-side resonant LCR circuit from the primary side via inductively coupled coils is interrupted, transmitted back to the primary side of the transformer and is there used for determining the resistance value by evaluating the time constant of the exciter response.

Abstract: An apparatus and method for measurement of ohmic loss and surface resistivity is provided with a straight lumen waveguide with at least one opening at one end. Diffraction of radiation introduced to the lumen at one end of the tube provides feedback to establish resonances within the tube. Using the "whispering gallery" resonant modes maximizes the total ohmic loss and thereby enhances sensitivity of resistivity measurements. The angle at which resonant radiation exits the lumen is a function of the mode and size of the operative. Thus, preferred spatial detection allows enhancement of the device signal while discriminating against undesired modes. Selection of modes allows high frequency measurements, into the tetraherz range, to be made without disabling restrictions in the device dimensions, spatial input/output coupling or ohmic loss depending on alignment for analysis of, for example, high temperature superconductors.

Abstract: The invention concerns a circuit arrangement for the combined application of an inductive and capacitative device (2, 3) for the non-destructive measurement of the ohmic resistance of thin layers. Such thin layers are, for instance, produced in high vacuum technology by evaporation. The inductive and capacitative devices (2, 3) are disposed in the immediate vicinity of the layer to be measured and are fed with a high-frequency voltage U.sub.HF. Since the inductive device (2, 3) has an oscillating circuit (4, 5) which is always continuously tuned to resonance, one is concerned with currents which flow both into the capacitative and the inductive devices (2, 3) and which are proportional to the conductivity of the layer to be measured. By evaluating these currents for which, according to the invention, the same circuity may be used, it becomes possible to make inferences about the surface resistance of the thin layer.